The present invention relates to a process for making a disposable diaper for absorption and containment of bodily discharges.
A process for making a disposable diaper has already been proposed in Japanese Patent Application Publication No. 1999-107007A. In this process, a continuous composite web is fed under a tension in a machine direction while a plurality of liquid-absorbent laminated panels each extending in a cross direction are fed at regular intervals in the machine direction onto an inner surface of the composite web and successively joined to the composite web.
More specifically, the process disclosed in the above-cited Publication comprises the steps of cutting transversely middle zones away from a continuous composite web along first cutting lines each describing a substantially circle to form a plurality of leg-holes spaced one from another by a given distance in the machine direction, placing the liquid-absorbent laminated panels on the continuous composite web and joining them to the composite web so that each of the liquid-absorbent laminated panels may be interposed between each pair of the adjacent leg-holes, and folding the composite web together with the panels along a longitudinal center line in two sections opposed to each other, joining the two sections opposed to each other in the vicinity of second cutting lines extending in the cross direction on both sides of each of the first cutting lines and then cutting the composite web along the second cutting lines to obtain a plurality of diapers arranged in the machine direction.
The composite web comprises a first web and a second web. The first web and the second web are overlapped together and respectively have inner surfaces opposed to and joined to each other by means of adhesives. Continuous waist elastic members extending in the machine direction and continuous leg elastic members extending in the cross direction are attached in a stretched state to the composite web. Specifically, the waist elastic members are attached to the composite web along its transversely opposite lateral zones. The leg elastic members are attached to the composite web between each pair of adjacent leg-holes formed through the composite web. The elastic members are interposed between the first web and the second web and attached to the webs by means of adhesives. In the diaper made by this process, the waist-surrounding upper end zone is defined by the transversely opposite side edge zones of the composite web.
According to the process disclosed in the above-cited Publication, the composite web comprises a pair of webs (i.e., the first web and the second web) placed upon each other along the transversely opposite lateral zones. Consequently, depending on a stretch ratio of the waist elastic members interposed between the webs, a contractile force of the waist elastic members remarkably act on the transverse opposite lateral zones of the composite web as the waist elastic members contract in the machine direction. In the individual diapers made by this process, therefore, the contractile force of the waist elastic members causes the waist-surrounding upper end zone defined by the transversely opposite side edge zones of the composite web to be formed with a plurality of crape-like irregular gathers. The crape-like gathers formed along the waist-surrounding upper end zone may be pressed against a wearer's skin and leave a compression mark on the skin. Such gathers may create a feeling of discomfort against the skin.